Personal lift or patient lift devices have been known and used in the past for the purpose of assisting with the mobility of otherwise immobilized patients. An attendant may help physically disabled patients who may suffer from a traumatic injury, a stroke, obesity, or another form of illness that renders them unable to move about. In many cases, such patients often are also too heavy to lift or, the attendant may not have enough strength to help the patient move.
Personal lift devices that have been used in the past typically include a strap or chain hanging down from a motor assembly, which in turn may be suspended from a movable stand or from a rail carriage riding along an overhead track. An overhead track can be arranged to dangle over a chair to permit the patient to be raised, suspended, and then moved along the track to a position where they can be lowered into a bed, bathtub or the like. Typically such patient lift devices are provided with a chair or sling that is positioned under the patient, and arranged to support the patient's bulk when hoisted from the chair or the bed. Examples of such slings A (FIG. 1) may be found in the following U.S. Pat. Nos. 1,536,766; 1,961,119; 2,272,778; 2,688,410; 2,739,783; 2,792,052; 2,835,902; 2,920,480; 3,123,224; 3,222,029; 3,234,568; 3,310,816; 3,699,594; 3,962,737; 3,998,284; 4,070,721; 4,117,561; 4,232,412; 4,633,538; 4,712,257; 4,723,327; 5,022,106; 5,072,840; 5,396,670; 5,530,975; 5,579,546; 5,787,529; 6,276,006; 6,289,534; 6,883,190; 7,240,621; 7,624,458; and 7,634,825, and Foreign Patents Nos.: CA 1,288,379; U.K. 2,223,477; and U.K. 2,184,706, which patents are incorporated herein by reference.
Also, patient handling mattresses are known in the art which include at least two flexible material sheets, that together define a plenum chamber, with at least one sheet being perforated with small pinholes over at least a central surface area, and which open up directly to the interior of the plenum chamber. Such prior art mattresses are used by arranging the perforated sheet so that it faces an underlying fixed, generally planar support surface, such as a floor or table. When the mattress is charged with pressurized air, the escape of air under pressure through the pinholes acts initially to jack a load placed upon the mattress above the perforated flexible sheet, and thereby creates an air bearing of relatively small height between the underlying fixed, generally planar support surface and the perforated flexible sheet. Examples of prior art transfer mattresses may be found in U.S. Pat. Nos. 4,054,960; 4,272,856; 4,517,690; 4,627,426; 5,065,464; 5,483,709; RE35,299; 5,561,873; 5,594,962; 5,598,593; 5,742,958; 6,073,291; 6,374,435; 6,415,583; 6,418,579; 6,677,026; 6,684,434; 6,687,935; 6,760,939; 6,857,143; 6,898,809, and published patent application No. 2002/0166168, which patents and applications are incorporated herein by reference.
There is a need in the art for an inflatable transfer mattress that also provides a patient supporting sling adapted to be manipulated from a non-planar or planar position to a patient supporting position, in which a seated patient may be suspended by straps from supporting points on a patient lifting device.